阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。
A
A powerful earthquake struck the northeastern coast of Japan at two forty-six p.m. local time on March eleventh.2011. Japan's Meteorological Agency released its first tsunami（海啸） warnings just three minutes later. The country has one of the best earthquake early warning systems in the world.
There are more than four thousand Seismic Intensity Meters in place throughout Japan to measure earthquake activity. These meters provide information within two minutes of an earthquake happening. Information about the strength and the center of the earthquake can be learned within three minutes.
There are also concrete(混凝土) sea walls around much of the Japanese coastline. But these measures proved no match for the powerful earthquake and tsunami.
